Vehicle interior finishing laminate sheet, process for producing the same, and apparatus therefor

Abstract

There are provided a vehicle interior finishing laminate sheet in which a polypropylene resin foam board of high foaming extent having interconnected cells is used as a core member, a vehicle interior trim material, a method for manufacturing the vehicle interior finishing laminate sheet, and an apparatus therefor. The present invention relates to a vehicle interior finishing laminate sheet 1 provided with a core member consisting of a polypropylene resin foam board 2 . The polypropylene resin foam board 2 is extrusion molded into a plate shape, and has an interconnected cell ratio of 50% or higher and a foaming extent of 10- to 50-fold. A plurality of polypropylene resin foam boards 2 , 2 are joined to each other by the hot plate welding method or the laser transmission welding method, whereby a large-size core member of vehicle interior finishing laminate sheet 1 , which is used for a roof lining or the like, can be formed.

The invention claimed is: 
     
       1. A vehicle interior finishing laminate sheet provided with a core member consisting of a polypropylene resin foam board, wherein the polypropylene resin foam board is formed from a non-crosslinked polypropylene resin exhibiting a strain hardening phenomenon in which the non-crosslinked polypropylene resin is elongated in a molten state and a viscosity of the non-crosslinked polypropylene resin rises suddenly before cutting, the non-crosslinked polypropylene resin having a semi-crystallization time such that crystallization begins before a highest viscosity of foamed resin is reached, wherein the polypropylene resin foam board is extrusion molded into a plate shape, and wherein the polypropylene resin foam board has an interconnected cell ratio of 50% or higher and a foaming extent of 10- to 50-fold. 
     
     
       2. The vehicle interior finishing laminate sheet according to  claim 1 , wherein a foaming extent is 30- to 35-fold. 
     
     
       3. The vehicle interior finishing laminate sheet according to  claim 1 , wherein the polypropylene resin foam board is formed with a skin layer on both surfaces thereof. 
     
     
       4. The vehicle interior finishing laminate sheet according to  claim 1 , wherein a sheet-shaped reinforcing material is provided on both surfaces of the polypropylene resin foam hoard. 
     
     
       5. The vehicle interior finishing laminate sheet according to  claim 1 , wherein
 a core member is formed by welding ends of a thickness side of a plurality of polypropylene resin foam boards each consisting of a plate body having a predetermined thickness; 
 the welding is performed by buttedly joining the polypropylene resin foam boards to form joints; and, 
 the joints are melted together by being brought into contact with a heated metal plate. 
 
     
     
       6. The vehicle interior finishing laminate sheet according to  claim 5 , wherein the vehicle interior finishing laminate sheet consists of the core member formed by joining the polypropylene resin foam boards formed with a concave part in a corner part of a joint surface disposed on an indoor side on opposed joint surfaces of the polypropylene resin foam boards. 
     
     
       7. The vehicle interior finishing laminate sheet according to  claim 1 , wherein the core member consists of a plate body having a predetermined thickness, and wherein the core member is formed by joining ends on the thickness side or the surfaces in a thickness direction of the plurality of polypropylene resin foam boards having a predetermined thickness by using a joint, and wherein the joint of the core member has a plane-shaped hardened layer which is heated by absorption of a laser beam. 
     
     
       8. The vehicle interior finishing laminate sheet according to  claim 5  or  7 , wherein the core member is formed by joining the plurality of polypropylene resin foam boards having a different foaming extent and consisting of the plate body having a predetermined thickness. 
     
     
       9. The vehicle interior finishing laminate sheet according to  claim 8 , wherein the core member is configured so that the foaming extent of the polypropylene resin foam board disposed on a side end part side is lower than that of the polypropylene resin foam board disposed on a center side. 
     
     
       10. The vehicle interior finishing laminate sheet according to  claim 5  or  7 , wherein
 the core member is formed with an opening; and, 
 the foaming extent of the polypropylene resin foam board disposed on a frame part side of the opening is lower than that of the polypropylene resin foam board disposed in any other part. 
 
     
     
       11. The vehicle interior finishing laminate sheet according to  claim 7 , wherein
 the core member is formed by joining the plurality of polypropylene resin foam boards, each consisting of the plate body having a predetermined thickness, in the thickness direction; and, 
 the foaming extent of the polypropylene resin foam board disposed on an indoor side is lower than that of the polypropylene resin foam board disposed on an outdoor side. 
 
     
     
       12. The vehicle interior finishing laminate sheet according to  claim 7 , wherein the core member is formed by joining the polypropylene resin foam boards with each other on opposed joint faces, and wherein the polypropylene resin foam boards are formed with an undulation.